This invention relates to electrostatic devices and more particularly to such a device having a resilient electrostatically-controlled variable electrode comprised of a plastic sheet carrying a thin metal film on at least one face and an electrical connection made thereto.
A variety of such devices are known. They are usually configured in such a way that the variable electrode is attracted to and moves to become coadunate with a fixed electrode when a voltage source is connected between the variable and fixed electrodes.
For example, in my U.S. Pat. No. 4,208,103 issued June 17 1980, such a device is described having a variable electrode made of a 0.00035 cm. thick plastic sheet, namely polyethyleneterephthalate (MYLAR, a Dupont Trademark), carrying a 500 angstrom thick aluminum film on both faces. Electrical connection is made to this film by a conductive epoxy resin joint to a wire lead.
A metallized-plastic variable electrode contacted by a pressure contact is described in my U.S. Pat. No. 4,094,590 issued June 13, 1978. There the end of the fragile variable electrode is crimp clamped to a sheet metal lead.
Such contacts to the delicate variable electrodes in the few electrostatic devices that may for example make up electrically controlled alpha-numeric signs can be adequately reliable.
However, when hundreds and thousands are used to form a matrix, such as a wall TV screen or a large array for displaying airline schedules in an airport lobby, a very high reliability is demanded.
It is therefore an object of this invention to provide a more reliable electrical contact to a delicate resilient variable electrode in an electrically actuated electrostatic device.
It is a further object of this invention to provide such an electrical contact that simultaneously lends itself to simplicity and ease in construction of a large array of interconnected electrostatic devices.